Electrified reversible surface mineralization of CO2 for direct air capture

[Geoengineering News]

https://www.nature.com/articles/s41560-026-01989-9

Authors: Zeyan Liu, Huajie Ze, Bosi Peng, Charles B. Musgrave III, Mohammad K. Shehab, Hyun Seung Jung, Hengzhou Liu, Kent O. Kirlikovali, William A. Goddard III, Omar K. Farha, Ke Xie & Edward H. Sargent 

13 February 2026

Abstract

Electrified CO2 capture and release from air offers net-negative emissions, but today’s liquid-carbonate-based systems have a high energy cost (6–10 GJ per ton of CO2), and organic sorbents are oxygen sensitive. Here we report electrified CO2 surface mineralization/demineralization capture/release, wherein an inorganic capture sorbent, MnO2, is electrochemically reduced/activated to generate Mn(III), which mineralizes CO2 to form MnOOCO2H (operando Raman); the process is reversed under oxidative potential. This approach is built upon Mn redox reaction that resides within the water-stable bracket, offering tunable driving force (kinetics/productivity) with applied potential (energy). After optimizing the electrochemical protocol, we capture from air (0.04% CO2 and 21% O2) at 4.1 GJ per ton of CO2, with capacity and kinetics comparable to prior sorbents, low sensitivity to oxygen/humidity, 80% single-pass CO2 capture ratio and release under a pure CO2 carrier gas stream and pressure drop <150 Pa. The system operates >1,000 h with >90% capacity retention and scales to 20 cm2 without loss; remaining challenges include material utilization, electrolyte, gas flow/pressure drop and CO2-purity management.

Source: Nature Energy